Musical instrument



April D. M. SOLENBERGER 1,853,999

MUS ICAL INS TRUMENT Filed March 5, 1929 3 SheetsSheet 1 INVENTOR flea)? M. 502677156) er ATTORNEYS April 1932- D. M. SOLENBERGER 1,853,999

MUSICAL INSTRUMENT Filed March 5, 1929 5 Sheets-Sheet 2 INVENTOR Jew/M Sale/2&6) a) ATTORNEYS April 12, 1932. D. M. SOLENBERGER 1,853,999

MUSICAL INSTRUMENT Filed March 5, 1929 3 Sheets-Sheet 3 I64)? M 502672262 er MAM ATTORNEYS Patented Apr. 12, 1932 DEAN M. SOLENBERGER, OF CLEVELAND, OHIO MUSICAL INSTRUMENT Application filed March 5,

The invention relates to stringed musical instruments of the type of the guitar, banjo or ukulele. It is the principal object of the invention to obtain a construction with which the playing is so simplified as to fall within the skill of the average person without special musical education. It is a further object to obtain a construction of silent key operated chord "playing mechanism which has sufficient scope to permit of the playing of most of the chords occurring in popular music and which is so compactly arranged as to neither detract from the appearance or interfere with the usual method of handling. Still further it is an object to obtain a construction which. is adapted for commercial manufacture at relatively low cost. With these and other objects in View the invention consists in the construction as hereinafter set forth.

In the drawings:

Figure 1 is a plan view of my improved instrument Figure 2 is a sectional side elevation thereof;

Figure 3 is a longitudinal section showing the key actuated mechanism;

Figure 4 is a sectional plan view thereof;

Figure 5 is a sectional bottom plan view thereof;

Figures 6, 7, 8, 9 and 10 are cross sections respectively on lines 66, 7-7, 88, 9-9, ]O 10 of Figure 3;

Figure 11 is a plan view of one of the selector plates;

Figure 12 is a plan view of the key board;

Figure 13 is an enlarged section similar to Figure 6 showing the bowing of two of the selector plates exaggerated.

Heretofore, certain constructions of stringed instruments of the guitar or banjo type have been provided with actuating keys for depressing the strings instead of the usual r finger operated fret board. Such constructions have, however, usually been quite limi ed in scope providing for the playing of only a few chords or where a larger number of keys are used, have become so complicated as to be scarcely practical. Furthermore, the application of such devices to the ordinary 1929. Serial No. 344,467.

finger board of stringed instruments makes an unsightly appearance and interferes with the usual handling. Vith my improvement, the keys and the mechanism actuated there by are so compactly arranged as to remain within the usual width of the finger or fret board and to project but a slight distance above tae plane of the strings. The mechanism is also of such character that to a great extent it may be placed beneath the fret board and within a hollow or chamber in the neck of the instrument. Thus the only portions which are above the plane of the strings are the string contactors and finger actuated keys, and these parts may be housed within a casing which largely conceals them and also acts to some extent as a silencer for the mechanism.

In the publication of popular sheet music for stringed instruments of the banjo and ukulele type it is usual to give in addition to the musical notation, a series of symbols designating the chords. These symbols are cross lines representing the strings and the frets of the instrument, together with dots indicating the position of the fingers to produce the chords when played on the ukulele. As my improved instrument is intended to produce a full musical chord by the depressing of a single key, I am enabled to facilitate the playing of the instrument by marking these keys with the corresponding chord symbol. Thus the performer who is not skilled in reading music can play the instrument by the reading of these symbols and the manipulation of the corresponding keys. While the symbols used represent a ukulele chord, it is sometimes desirable to substitute a banjo chord which is different but equally harmonious. Instead, however, of substituting a different symbol for this banjo chord, the ukulele symbol is still retained, as this is the one which is printed on popular sheet music. The same is true of a guitar where the chords played differ from those of either the ukulele or banjo but can be substituted therefor without loss of harmony.

The number of distinct chords that can be produced on a stringed musical instrument is practically without limit. However, in

popular music there is not such a large number of chords generally used, and of those used certain chords occur much more frequently than others. I have therefore selected for my instrument such chords as are found in published popular music and have provided a sufficient number of keys for the playing. of these chords. I have also lim ited the number of necessary keys by selecting certain chords which may be used as substitutes for others without greatly modifying the character of the music. Thus my key board is selected to produce first, chords most frequently used, second,chords less frequently used but still occurring in popular music, third, substitute chords for chords sometimes occurring but which would, if individually produced, necessitate a larger number of keys thandesirable. I also preferably arrange this key board so that the most frequently used keys are in the most convenient position for operation.

The range of the instrument may be increased by different tunings of the strings, as for instance one tuning for music written for the ukulele, another tuning for banjo music, etc. I also find it desirable to shorten the length of the fret board from that used in a standard banjo so that the higher tuning'may be obtained without too great stressing of the strings.

As specifically illustrated, A is the head of a banjo and B the neck portion or what is usually termed the fret or finger board. As has been stated, I preferably reduce the length of this neck portion so as to have strings of shorter length than in the standard banjo, but longer than is used in the ukulele or mandolin. The length preferably used is twenty inches measured from the nut on the banjo neck to the string bridge. The portion of the neck which is adjacent to the ey head C is formed hollow beneath the fret board D to provide a chamber E for the mechanism operated by the keys F. Above the fret board and the strings passing over the same are arranged finger actuated keys F and a series of string depressing levers or contactors G, preferably a sufficient number of the latter to control all of the strings and adjacent to three separate frets. These three positions will be suflicient for the production of all of the chords essential to the instrument.

I have found from the analysis of popular music for instruments of this kind that a maximum of twenty-one keys will be sufiicient. In three different tunings of the strings these keys will produce a total of sixty-three chords which, by the use of certain substitutes will meet all requirements. I preferably arrange all of the keys in three parallel rows of seven each running longitudinally of the fret board or seven rows of three each extending transversely of the fret board. The chords which I have selected to be produced by these keys and the preferable arrangement of the keys are as follows:

From left to right transversely of the fret board and in successive rows from top to bottom are E, D F, A B C B flat, C, G a min., d min, g min; 0 min., f min. b fiat min.; A flat, G Aug, D flat; F sharp dimF, G sharp dimF, C sharp dimf. I also preferably designate the keys by numerals which run in the same sequence from 1 to 21. Thus the player may learn to associate the chords produced by the keys either with the symbol represented or the numeral.

As has been stated, all of these chords can be formed by the use of three frets and open strings in a four stringed instrument. For depressing the strings into contact with the frets, I have provided three groups of string contaetors G adjacent to the respective frets, each group having a contactor for each string or twelve in all. To produce the chords, these contactors G must be operated in various combinations and each of these combinations in turn must be actuated by a single key. Therefore, the mechanism for accomplishing such result must include connectors corresponding in number to the string contactors G which connectors must be adapted for operation singly or in combinations by the various keys F.

It is very important that this mechanism should be made with the elements thereof in close fitting relation and without the capability of independent vibration which inevitably results in a hum or disturbing noise when the instrument is being played. To accomplish this result I preferably form the fret board of a metallic plate having the frets accurately positioned thereon and then mount the chord playing mechanism upon this plate and in fixed relation thereto. To avoid any unnecessary projection beyond the usual contour lines of the instrument a considerable portion of the mechanism is preferably arranged below the fret plate and in the hollow or recess E in the neck portion, the detailed construction being as follows:

Each of the keys F is in the form of a bell crank lever having a laterally extending actuating arm F terminating in a finger bearing or button F and also provided with a depending actuated arm F 3 passing through a slot in the fret plate into the chamber E. The three longitudinal rows or banks of keys are arranged parallel to each other and to produce the most compact arrangen'lent while still giving sufficient bearing area for the fingers the key buttons are preferably of rectangular or parallelogram form. This permits of arranging them in very close proximity to each other without interference. The buttons are also preferably provided with curved upper surfaces which may be either simple curves, concave or convex, or

may be spherical or dome shaped. This permits of readily sliding the fingers from one button to another and the centers of curvature are so arranged that the highest point in the surface is displaced from the center of the area towards the outer end or away from the fulcrum of the lever. Thus when the key is depressed this in some measure compensates for the change in angularity thereof.

The contactors G are also preferably in the form of bell crank levers having the laterally extending arms G arranged substantially parallel and adjacent to the string to be operated and terminating in a transversely projecting pin G preferably surrounded with a rubber sleeve G for contacting with the string. These levers are preferably formed of spring steel and the arm G is restricted in width sufficiently to permit of a slight flexing so that if one contactor should be moved against the fret plate in advance of another it will flex to avoid holding the latter from fully seating.

The contactors G are also provided with depending arms G which project through apertures in the fret plate and into the recess E. All of the keys F are grouped below or further inward on the fret board than the contactors G and are connected to the latter through a series of selective connector plates H arranged beneath the fret plate and in the recess E. These connector plates H may be made of thin sheet metal and may be held properly spaced and guided in their movement by a series of guide posts I depending from the fret plate D. These posts are grooved to form a series of annular spacers or guide flanges 1' between which the plates H are slidably held. The plates H are preferably formed of spring metal which is slightly arched to be placed under tension when engaged with said guides whereby it is held from rattle or noise producing vibration. At their lower ends the posts I have connected thereto a plate J which imparts rigidity to the frame and also forms an anchor for springs as hereinafter set forth.

The fulcrum bearings for the keys F and contactors G are formed by cross-shafts or pins K and K which are preferably secured to upturned side flanges L formed integral with the fret plate.

The fret plate D is slotted for the passage of the depending portion of each bell crank lever and to prevent any rattle or hum each lever is resiliently pressed against one side of the slot through said plate. As shown, the resilient pressure is supplied by a series of spring arms L which are struck out from side flanges of a sheet metal channel plate L riveted or otherwise secured to the lower face of the fret board and between rows of keys and string contactors.

Y The connector plates H correspond in number to the string contactors G and each plate is apertured for the passage of all of the depending arms of both the string contactors G and the keys F. Most of these apertures or slots M are of suflicient length to permit the free movement therein of the depending arm but one of the string contactors is connected to each plate so as to be operated thereby. One or more of the keys is operatively connected to each plate so that whenever any one of such keys is operated it will move the 9 plate H longitudinally, thereby actuating the str ng contactor and depressing one of the strings adjacent to its corresponding fret.

Thus it will be understood that the plates H operate as selectors determining which of the keys will actuate a particular string contactor. On the other hand, each key may simultaneously actuate a number of the plates H and their corresponding string contactors to produce a particular chord. Each plate is resiliently held in its normal position by a spring N preferably connected to one end thereof and the springs N are anchored on posts 0 extending between the fret plate D and the plate J. Inasmuch as some of the g keys actuate only a single plate and contactor while other keys actuate from two to four of said plates and contactors, it is obvious that the springs N will place a different tension or resistance upon different keys. compensate for by additional springs P which are attached to the lower ends of the arms F of some of the keys F, said springs being anchored to hooks J struck out from the plate H J. These sprmgs are ad usted in tension so that the sum of the resistance of one or more of the springs N and the compensating spring P will be equal for each key.

The portion of the mechanism which exe tends up above the fret plate D is preferably housed both for the purpose of concealing the same and for mufiling any slight sound that might be produced by this operation. This housing is preferably formed of pressed sheet metal so as to cover all of the contactors G but being cut away for the projection therethrough of the key buttons F As these buttons are parallelogra-ms arranged in close proximity to each other, it is unnecessary to have individual openings in the housing, but the entire group is placed in a single opening. The cover Q, is held in position by engagement with the upturned flanges L and by spring catches Q, engaging recesses in said flanges. Thus the cover may be easily removed at any tune for access to the mechanism.

The construction as above described can be very accurately made as it is chiefly die work and all of the parts can be assembled before mounting upon the neck of the instrument. This mounting is accomplished by securing the fret plate D by screws D or by any other suitable means. When completely assembled This 1 ll iris all of the mechanism is concealed, the key buttons alone being exposed to view.

WVhat I claim as my invention is:

1. In a stringed musical instrument of the guitar or banjo type, the combination of spring actuated string contactor mechanism, a fret plate and a neck portion with a recess therein below the same for accommodating portions of the mechanism.

2. In a stringed musical instrument of the guitar or banjo type, the combination of a plurality of keys, mechanical parts for fretting said strings, actuated thereby, certain of said parts being slightly arched to obtain resiliency and prevent noisy sympathetic vibration with the instrument strings.

3. In a stringed musical instrument of the guitar or banjo type, the combination of 21 fret plate having a plurality of frets thereon, mechanism comprising a plurality of string contactors mounted on said plate and arranged in operative relation with the frets, keys also mounted on said plate arranged in a plurality of banks or rows substantially oifset from said c-ontactors longitudinally of the instrument neck, and connectors between said keys and contactors for operating the latter.

4. In a stringed musical instrument of the guitar or banjo type, the combination of a plurality of frets and mechanism comprising a plurality of hell crank lever string contactors arranged in operative relation to the frets, a plurality of bell crank lever keys and selective connectors between bell crank arms of said keys and contactors for operating the latter.

5. In a stringed musical instrument of the guitar or banjo type, the combination of a plurality of frets and mechanism comprisinga plurality of string contactors arranged in operative relation to the frets, a plurality of individual bell crank lever keys and selective connectors between bell crank arms of said keys and the contactors for operating the latter.

6. In a stringed'musical instrument of the guitar or banjo type, the combination with a plurality of frets, of a plurality of string contactors arranged in operative relation to the frets, a bank of keys for actuating said contactors, each key being of parallelogram form and arranged in close proximity to adjacent keys, and an enclosing casing having a single opening for all of the keys of the bank.

7 In a stringed musical instrument of the guitar or banjo type, the combination with a plurality of frets, of a plurality of string contactors arranged in operative relation to the frets, a bank of keys for actuating said contactors projecting upward above said frets, and a removable casing for enclosing the space between said keys and frets and having a single opening in its top for access .to all of the keys.

8. In a stringed musical instrument of the guitar or banjo type, a plurality ofbell crank lever keys and a plurality of hell crank lever string contactors, and plurality of laterally extending connectors between said keys and string contactors, and resilient means attached to said connectors for overcominginertia and friction and facilitating quick return of the parts.

9.. A stringed instrument of the guitar or banjotype provided with a hollow neck portion, a fret plate forming a cover for the hollow, and mechanism including a plurality of string contactors in operative relation to the frets of said plate, a plurality of keys, and connections between said keys and contactors for operating the latter in different combinations, a portion of said mechanism being arranged beneath said plate within the hollow.

10. In a stringed musical instrument of the guitar or banjo type, the combination of a fret plate and mechanism mounted on said fret plate comprising a plurality of string. contactors arranged in operative relation to the frets of said plate, a plurality of keys, connectors between said keys and string contactors for operating the latter singly and in combinations, and means for equalizing the resistance to the operation of the keys which actuate diflerent numbers of strings.

11. In a stringed musical instrument of the guitar or banjo type, the combination of a plurality of keys, connectors, string contactors, and resilient means for restraining each of the elements of said mechanism from discordant noise producing vibrations.

12. A chord playing mechanism for stringed musical instruments of the guitar or banjo type comprising a plurality of keys,

each key being marked with a standard uku-' lele fret symbol or chord marking, and mechanism actuated by each of said keys for fretting a chord which is one of the corresponding and substitute chords respectively for the banjo, ukulele or guitar.

13. A banjo having the neck portion thereof substantially shortened from standard length, and having a restricted number of frets and a key actuated chord producing mechanism cooperating with the said frets, the diminished length of said neck permitting of a higher than normal tuning of the strings without over-stressing the same.

14;. A chord playing mechanism for stringed musical instruments of the guitar or banjo type comprising a plurality of hell crank lever keys having a relatively short stroke whereby the angle of said keys when depressed is but slightly altered.

15. A chord playing mechanism for stringed musical instruments of the guitar or banjo type comprising a plurality of hell crank lever keys having a stroke of less than three-thirty-seconds of an inch whereby said keys when depressed will be but slightly altered in angle.

16. In a stringed musical instrument of the guitar or banjo type, the combination of a plurality of frets, mechanism mounted on the instrument handle, including a plurality of string contactors in operative relation to the frets, a plurality of keys above said frets and connections between said keys and contactors for operating the latter in different combinations, portions of said mechanism being arranged below said frets.

17. A stringed instrument of the guitar or banjo type provided with a hollow neck portion, a fret plate covering the hollow in said neck portion and mechanism including a plurality of string contactors in operative relation to the frets of said plate, a plurality of actuating keys, and selector connectors between said keys and contactors for operating the latter in different combinations, a portion of said mechanism being arranged above said fret plate and a portion arranged beneath said plate and within said hollow.

18. In a stringed musical instrument of the guitar or banjo type, the combination with a plurality of frets over which the strings eX- tend, of string contactors mounted in operative relation to said frets and having actuating arms projecting downward, chord playing keys also mounted above said frets and having depending arms extending downward, and mechanism concealed in the instrument neck for connecting said key arms with said contactor arms to produce various combinations.

19. In a stringed musical instrument of the guitar or banjo type, the combination with a fret plate, of a plurality of stringed contactors and actuating keys all in the form of bell crank levers fulcrumed in rigid relation to said plate and having arms projecting through apertures therein and selective connectors between said keys and contactors formed of a series of plates arranged in close proximity to each other and parallel to said fret plate, said plates being apertured for the passage therethrough ofthe arms of said contactors and keys being in operative relation to certain of said arms and providing clearness for the independent movement of other of said arms whereby said contactors and keys are selectively connected in various combinations.

20. In a stringed musical instrument of the guitar or banjo type, the combination of a plurality of string contactors, a plurality of keys, connecting means through which different keys actuate different numbers of contactors and means to equalize the amount of finger pressure required for the operation of each of said keys.

21. In a stringed musical instrument of the guitar or banjo type, a chord playing mechanism comprising a plurality of keys, string contactors and connectors, each element of said mechanism which is relatively movable to an adjacent element being resiliently held in contact therewith to restrain independent discordant noise producing vibrations.

In testimony whereof I aiiix my signature.

DEAN M. SOLENBERGER. 

